Multi-use work head for grinding operations



April 30, 1963 H. A. ROMBOLD 3,087,287

MULTI-USE WORK HEAD FOR GRINDING OPERATIONS Filed Sept. 26. 1960 3 Sheets-Sheet 1 b HARRY J KSKAESLD WWW ATTORNEY A ril 30, 1963 H. A. ROMBOLD 3,087,287

MULTI-USE WORK HEAD FOR GRINDING OPERATIONS Filed Sept. 26. 1960 3 Sheets-Sheet 2 INV EN TOR. HARRY A. ROMBOLD "mm/Mu ATTORNEY April 30, 1963 H. A. ROMBOLD 3,087,287

MULTI-USE WORK HEAD FOR GRINDING OPERATIONS Filed Sept. 26. 1960 3 Sheets-Sheet 3 INVENT HARRY A. ROM D ATTORNEY United States Patent 01 3,087,287 MULTI-USE W QRK HEAD FOR GHNDING OPERATION Harry A. Rombold, 2143 Woodlawn Ave, Glenside, Pa. Filed Sept. 26, 1960, Ser. No. 58,393 1 Claim. (Cl. 51-225) This invention relates to improvements in grinding machinery in general, and specifically to improvements in cutting tool holding devices which cooperate with such grinding machinery.

The relative positions of the cutting-tool to be ground or dressed and the grinding element of the machine usually determines the result of the grinding operation. In a cutting-tool gumming operation, for example, when a chip clearance channel of uniform depth and even surface is required, both position and continuity of the grinding operation determine the resulting etficiency of the ground tool. An important object of the present invention is therefore to provide a cutting-tool holding fixture that has novel means for adjustably positioning the cutting-tool to be ground or dressed in angular relation to the selected operating surfaces of the grinding element.

And yet a further object is to provide a cutting-tool holding fixture that can be adjustably positioned relative to the grinding element to produce the best grinding operation for the efliciency of the said cutting-tool with greater ease, speed and precision than has been previously possible.

A further object is to provide a cutting-tool holding fixture in which a cutting-tool can be securely fastened, adjusted and indexed for repeated, accurate grinding operations.

Other objects and advantages of the present invention will be apparent by reading the following specification with reference to the accompanying drawing forming a part thereof. It will be understood that modification may be made in the structural details described and illustrated, without departing from the spirit of the invention as defined in the appended claim.

Reference to the drawings in which like reference numerals indicate like or similar parts:

FIGURE 1 is an elevational view, in perspective, of a typical grinding machine with which the invention is used.

FIGURE 2 is an exploded view, in perspective, showing one assembly of the elements of the invention.

FIGURE 3 is an exploded view, in perspective, showing an alternate assembly of the elements of the invention.

FIGURE 4 is an elevational view, in perspective, of the elements shown in FIGURE 2 assembled in a grinding operation.

FIGURE 5 is an elevational view, in perspective, of the elements shown in FIGURE 3, assembled to illustrate a variation of the grinding operation.

The precision required in grinding operations presents the specific problem of relative positions between the work piece and the grinding element. This is particularly true when cutting-tools such as milling cutters which are used in milling steel are the work pieces to be ground. One such grinding operation is that termed gumming by which is meant grinding a chip space or a chip clearance and face in hardened. highspeed shanked-end milling cutters, and angle milling cutters, side cutters and face cutters. The fixture described here has particular advantage in this operation.

It has long been the practice to gum a chip space or dress a milling cutter on a grinding wheel by holding the cutter or work piece in the hands of the grinding operator. The Wheel is approached at the most convenient exposed part of the shaped periphery and a series 3,687,287 Patented Apr. 30, 1963 of grinds are made. An effort is made to obtain the best chip clearance and face obtainable from observation.

The result is dependent on the skill of the grinding operator, and at best is formed by a series of faces which affect the efiiciency of the cutting-tool. The fixture described below reduces the grinding operation to a simple face and continuous chip clearance of even, preselected depth and angles greatly increasing the milling tool efficiency.

Referring now to the drawing and particularly to FIG- URE l, a typical grinding tool 10 is shown, mounting the head 12 or" the invention in operating relation with grinding wheel 14, protected by a guard or cover 16. A motor mount 18 to drive the grinding Wheel 14 may be moved into position with the Work piece, shown here by the number 2@, as by a transverse traversing screw, not shown but operated by hand wheel 22. A longitudinally traversing screw, also unseen, is operated by hand wheel 24 to position the motor mount 16 at the proper longitudinal position on bed 26. A power table traverse moves table 28 into and away from contact with grinding wheel 14. Control lever 30 controls the table movement.

The movable table 28 is adapted to support and hold head 12, and the contained work-piece 20, in predetermined relation with grinding Wheel 14. As illustrated in FIGURE 1, and detailed in FIGURES 2 and 3, as well as in FIGURES 4 and 5 later described in detailing the grinding operations, head 12 is mounted in adjustable relation to both the table 28 and grinding wheel 14. In all the figures of the drawing all like elements are shown by the same numbers.

An angle plate 32, shown in every figure of the draw ing, is secured to movable table 28 as by a bolt 34 extending through slot 36 in horizontal leg 38, fastened by nut 49. (FIGURES 1, 4, and 5.) Two push pins 42, shown in FIGURES 2 and 3, are aligned with the table slot into which they fit, and are the means for rapidly regaining a previously established alignment. Set screws 44 fasten push pins 42 as desired. Vertically extending leg 46 of angle plate 32 is apertured as at 4-8 to receive bolt 50, and the aperture is further enlarged to receive a bushing, lug, or boss, as at 52 for more rigid connecting of mating elements. A cylindrical scale 54 indexed around the peripheral face as shown at 56, affords exact angular adjustment in the vertical, longitudinal plane of the grinding machine as diagrammed in FIGURE 1.

Element 60, a right-angle connector termed a knee in machine shop practice, is adapted to engage the vertically extending leg 46 of angle plate 32 as an intermediate supporting means. Boss 62, extending from leg 64, fits enlarged aperture 52 and is blindly secured by bolt 50. A point of origin 66 is stamped to cooperate with index 56 aifording exact angular adjustment longitudinally of the grinding machine. Completing the structure of this angular knee, connecting means or leg 68 is at right angles to leg 64, and is apertured as at 76 to receive bolt 72. Aperture 70' is further enlarged as at 74 to receive a bushing, lug or boss as above described for another connection, enabling easy, exact and firm assembly. Also a cylindrical face 76 is marked in degrees to afford exact adjustment transverse the bed of the grinding tool and at right angles to the longitudinal adjustment described above.

FIGURES 2 and 3 operably position backing plate 80 in relationship with the connecting elements of the assembly. In this exploded illustration, the shape and construction of backing plate 80 is made clearer, as is its relation with the other elements of the assembly. Further, it is believed FIGURES 2 and 3 Will be more readily understood.

Backing plate 80 is the means for operably connecting head 12 in proper relation to the grinding wheel 14 for the grinding operation. In the upper portion of backing plate 80, an aperture 82 enlarged at 84 to receive a connecting means such as a bushing 86, permits easy connection with knee 60 (FIGURE 2), or directly to angle plate 32 (FIGURE 3). A set screw 88is set into the outer edge of the bushing head, as shown, to lock when assembled. Bolts 50 or '72 engage bushing 86 depending on which grinding assembly is required, FIG- URE 2 or FIGURE 3. A stampmark 91) provides angular setting relations with degree scales 56 or 76, again depending on the assembly selected.

A dove-tail slide 92, raised on one face of backing plate 81 is adapted to engage a similarly shaped groove on the engaging face of head 12, this association to be fully described later. A slotted aperture 94 receives two bolts 96 'which pass into drilled and tapped holes in head 12 and position backing plate 81) and the head in adjustable relation to each other. As will be fully understood later, when the operation of the device is fully described, the relative adjustability of the backing plate and the head, is most important in performing the grinding operations of this fixture.

Referring again to FIGURES 2 and 3, head 12 is detailed and positioned to make both assembly and function clear. As explained above, the engaging face of head 12 is fashioned to cooperate in adjustable relation with backing plate 80'. In the illustrated elements, dove-tail slide 92 of backing plate 80 is fashioned to a slidable fit into dove-tailed slot 109 in head 12. Drilled and tapped holes, not seen, are positioned to receive setting bolts 96 through slot 94-.

Also unseen, but indicated by the relation and alignment of work-piece 20, head 12 is drilled to receive the shank of work-piece 2t and, by means of set-screw 102, can be locked in place. An index ring 104 is slide-fitted over the shank 21 of workapiece and is locked in a selected position relative to the notches 112 in the ring and the grinding operation to be accomplished by a set screw 105, and rotatably positions the piece in the head for grinding wheel operations. A trigger block 106 with cooperating spring retained trigger 108 and engaging lug 110 fits into the notches 112 of index ring 104- and rotatably positions work-piece 20 for cutting by the grinding wheel 14. Finally, head 12 is fitted with a drilled and tapped hole through the base permitting a bolt 114 (FIGURE 2) to be rotated and enter into the head to bear against the bottom of the work-piece, regulating the depth to which the work-piece is seated, and also by further rotation to press harder on the bottom of the work piece to gradually break the suction which could interfere with removal from head 12.

Before turning to a description of the operations of two separate assemblies serving diiferent grinding operations and illustrated in FIGURES 4 and 5, it is necessary to fully describe FIGURE 3. In this latter figure, an exploded detail such as shown in FIGURE 2 is illustrated. In fact all the elements except the knee 60 are required to serve this grinding purpose. The omission of knee 60 permits movement of the work-piece into grinding relation with the assembly shown in FIGURE 2. For example, conical cutters requiring a continuous surface and chip clearance from apexto base can readily be dressed by use of this assembly (FIGURE 3) of the fixture. On the other hand, a cylindrical cutter such as shown by work-piece 20, requires the elements of the fixture shown and arranged as in FIGURE 2.

FIGURE 3, considered together with FIGURE 5,

- show-s the angle plate 32 as the initial mounting element dove-tail components and adjusted into position before tightening bolts 96. In thisinstance the workpiece is one which requires a different type of grinding than that discussed as work-piece 20, and must be positioned to approach the grinding wheel in a different plane and at a diiferent angle. The index ring 104, indexing trigger 108 and locking set screw 102, all serve the same purpose, as previously described for FIGURE 2.

FIGURES 4 and 5 show diagrammatically the advantages in the grinding operations for each of the two assemblies detailed above. By adjusting the work-piece below, and in angular relation (in two planes) to the preshaped edge of the grinding wheel shown in FIGURES 4 and 5, grinding movement from the edge of the tool (work-piece) to the center as indexed and controlled, will produce a perfectly gummed cutting tool. The chipspace is completed in a single pass of the Wheel; it is of constant depth being moved adjacent the lower grinding wheel tangent, and perfectly angled for slope both toward the tool center, and as an under-cut for chip clearance.

FIGURE 5 illustrates the adaptability of the disclosed invention where a ground face of pre-deterrnined contour, yet constant un-marred surface is required. In the illustration, a conical cutter is shown as the subject of the grinding operation, and a pre-shaped grinding wheel is used. Again the disclosed fixture must be adjusted to approach the cutting tangent of the wheel which gives a finished face of selected contour without a surface blemish in the chip space. This is accomplished as is evident from the above detailed description.

From the above, it will be evident that the complete fixture as described in relation to FIGURE 2 especially, provides the means for accomplishing the required operations on most cutters used in the metal shaping industry. The results obtained by using the described fixture produces a simplified grinding operation which eliminates all errors found in the present procedures of manual grinding. Once established, the same surfaces can be reproduced regardless of interruption or discontinuance of the grinding operation, once started.

This fixture by using additionally supplied standard equipment furnished with grinding machines, will also exactly and as efficiently grind the chip spaces (cutting faces), of side cutters, insert tooth cutters, shell mills, shell reamers, and a multiplicity of like metal cutting tools. By further adding draw-ring type collets it can be adapted to grind special and complicated indexed punches, such as triangular, hexagonal, octagonal, square and rectangular in shape, with the same case, efficiency and exactitude. All of these adaptabilities will be readily and fully understood by those versed in the art. It will be further understood that it is here intended to cover all changes and modifications of the examples of the invention chosen here for the purpose of illustration which do not constitute departures from the spirit and scope of the invention as disclosed in the claim appended hereto.

I claim:

In combination, a grinding device comprising a support mounting a generally horizontal bed having a slotted longitudinal guideway, slide means comprising a horizontal base and an integral centrally a-pertured upstanding plate, said base having aligned lugs which are received in the guideway for maintaining the slide means in a fixed rectilinear path during its movement along the guideway, a slot in said base extending normal to the upstanding plate, a first locking bolt means extending through said slot for releasably interconnecting the slide means to the bed to permit both longitudinal and transverse adjustmentsof the slide means relative to the bed, a connector comprising a centrally apertured first plate and an integral centrally apertured second plate disposed normal to each other, a second locking bolt means extending through the central aperture of the upstanding plate of the slide means and the central aperture of said first plate of the connector, said second locking bolt means releasably interconnecting the slide means and connector and permitting rotative adjustment of the connector, a tool holding unit including an apertured backing plate and a tool socket, means interconnecting the backing plate and socket and permitting adjusted rectilinear movement of the socket, other means carried by the backing plate for securing the socket to the backing plate in adjusted position, a third locking bolt means extending through the aperture in the backing plate and the central aperture of the second plate of the connector, said third locking bolt means releasably interconnecting the tool holding unit with the connector and permitting rotary adjustment of said unit relative to the connector, said socket having means permitting rotative adjustment of a tool received therein from one operative position relative to a grinding wheel to selected operative positions and means for locking the tool in an adjusted position.

References Cited in the file of this patent UNITED STATES PATENTS Van Norman Aug. 3, Goodhew et al Nov. 15, Dobyne Apr. 2, Sneva May 27, Elliott et al. July 19, Rocheleau Oct. 11, Shifando Apr. 9,

FOREIGN PATENTS Germany May 17, 

